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Devil’s-bit scabious pratensis

Devil’s-bit scabious is part of the teasel family () and has the familiar pin-head cushion flower associated with this group of . It can grow up to 1 m and has a basal rosette of obovate leaves that are not toothed at all, and stem leaves arranged in opposite pairs (unlike the similar common knapweed leaves that have tiny dark projections around the edge and stem leaves arranged alternately). The mauve – dark purplish-blue florets are arranged in a pin cushion and the flower tubes has four lobes all of equal length (unlike field and small scabious that have flower tubes with 5 lobes and an outer circle of florets with longer lobes). It also has a local name of ‘blue button’ in Northern Ireland where is it particularly common in rush pasture.

Lifecycle

It is usually one of the later flowering plants blooming between June – October. Devil’s-bit scabious is a nectar-rich flower used by many pollinating insects, and is the main caterpillar food for the butterfly Euphydryas aurinia and the larvae of narrow- bordered bee hawk-moth .

The name 'scabious' derives from 'scabies', one of the many ailments that flowers bearing this name were supposed to help cure. It has short and stubby roots, and one legend around the plant is that the Devil grew angry about the Devil’s-bit scabious distribution across Britain and Ireland medicinal properties and tried to get rid of it The data used to create these by biting the roots off, hence 'devil's-bit' maps has been provided under licence from the Botanical Society scabious. of Britain and Ireland (BSBI) and accessed from the Society’s online distribution database.

Habitat drainage prior to agricultural improvement, particularly purple moor grass and rush Devil’s-bit scabious lives in a range of habitats pasture. including neutral, calcareous and acid grasslands, purple moor-grass and rush Lack of management is also a factor. The pasture, fens and damp woodlands. decline of livestock grazing on wetter pastures allows the build-up of grasses which, Distribution over time, out-compete and shade out the wildflowers including devil’s-bit scabious. Devil’s-bit scabious is widespread across Some grassland management is required to Scotland, Wales and England except around maintain suitable habitat conditions for this the Wash estuary. It has a more patchy species to thrive alongside other wildflowers. distribution in Northern Ireland and the Irish Republic. Survey method

GB status and rarity There is no strict survey method for devil’s- bit scabious as it is usually monitored as part The Red Data List for Great of grassland communities. It can be monitored Britain (2005) and the Irish Red Data Book using a range of methods, such as National (1988) do not list devil’s-bit scabious and it is Vegetation Classification surveys used to considered to be common. describe the overall vegetation of community, Common Standards Monitoring used to Marsh fritillary is listed under Section 41 monitor Sites of Special Scientific Interest or (England) and Section 42 (Wales) of the the adapted Rapid Assessment which is similar Natural Environment and Rural Communities and is being used on non-designated Act (2006) as a ‘species of conservation wildflower grassland and grasslands that are concern’, and it is on the Scottish Biodiversity being restored. List and on the Northern Ireland Priority List. Where marsh fritillary is present or a Protection under the law reintroduction of this butterfly is being considered, the cover of devil’s-bit scabious Devil’s-bit scabious is not specifically may be monitored using quadrats by protected under any law in any of the estimating the percentage within each countries. square. More often, there will be direct monitoring of marsh fritillary caterpillar food Marsh fritillary is fully protected under the webs which will be on devil’s-bit scabious Wildlife and Countryside Act (1981) and rather than monitoring of the plant. Wildlife (NI) Order 1985. Habitat management for devil’s-bit scabious Reasons for decline Devil’s-bit scabious is a late Devil’s-bit scabious is a plant of species-rich and usually starts to bloom when other calcareous, neutral and acid grasslands which wildflowers are setting seed. As a have significantly declined during the second consequence, hay cutting which is usually half of the 20th Century. The loss of these taken in July or early August may remove the grasslands is associated with an increase in flower heads preventing the species from agricultural production and intensification of setting seed and over time it will decline in management on grasslands, including most hay-cut meadows. Management for changing from traditional management to devil’s-bit scabious should concentrate on a silage production which often involves over- pasture regime aiming to create a varied seeding with faster-growing nitrophilous vegetation height between 8-25 cm at the end grasses and legumes, fertilising meadows and of the autumn grazing period. This can be using herbicides to reduce agronomic weeds. achieved through extensive grazing of pulse / Wetter habitats have often been subject to mob grazing.

For more information on managing grassland Devil’s-bit scabious is a slow-growing as pasture, see the advice note on how to perennial and may take several years to reach manage a hay meadow or grazing pasture. maturity and flower. If it is part of the seed There is specific management advice for mixture or was present and flowering at the purple moor-grass and rush pasture which can time when green hay or brush harvested seed be found under the acid grassland section of was taken, then it is worth waiting for 5-6 the managing for grassland habitats and years to observe whether seed has germinated marsh fritillary butterflies which can be found and seedlings have survived to maturity. If under the butterfly section of the managing there was not any devil’s-bit scabious present for grassland species. it can be grown as plug plants for transplantation into the grassland or Growing devil’s-bit scabious for additional seed could be sown. See the reintroduction advisory notes on meadow enhancement using plug plants and meadow enhancement sowing As devil’s-bit scabious is late flowering it additional seed for further information. There tends to be missed in seed harvested as green has been no reported difficulties germinating hay, as this is usually taken at an earlier time seed suggesting that it is unlikely to require of year just as the majority of species are scarification (light abrasion of the seed to setting seed, and can be missed with brush- help water penetrate and trigger harvesting if the field is swept too early and germination), and it is not known whether it there is not a later harvest. As a requires vernilisation (periods of freeze-thaw consequence, seed mixtures may not contain over the winter to trigger germination). much devil’s-bit scabious seed. However, it is recommended that seed is sown in the autumn, which is the usual time that wildflowers naturally shed seed.